The World Record for Fasting

Himanshu Sharma, MD's commentary unravels human resilience, where it comes to fasting.

Some of you may wonder, what is the world record for fasting?

Angus Barbieri was a Scottish man who fasted for 382 days, from June 1965 to July 1966. He lived on tea, coffee, soda water and vitamins while living at home in Tayport, Scotland. He lost 276 pounds (125 kg) and set a record for the length of a fast.

During this fast, he never got hypoglycemic (low blood sugar). How is that possible you may wonder? Well, we have existed for centuries in environments that have ranged from the arctic tundra to the tropics, with no guaranteed meals.

We have biochemical pathways that allow us to create glucose from non-carbohydrate substances. This process is called ” gluconeogenesis”.

These substrates include glycerol from triglycerides (fats) and amino acids. This is the secret to Angus Barbieri’s survival.I myself have been able to fast for up to 96 hours, with continued strength training and have had no issues whatsoever. Unless and until you have some external factors like insulin/diabetic medications on board you will not have hypoglycemia in the midst of a fast.


The other fear that I often hear is the fact that fasting will make you lose muscle.

Do really think the human body is so poorly designed that it stores all this fat for emergencies but chooses to burn muscle instead, when the time comes? This is no different than you saving firewood for a winter storm, yet choosing to burn the sofa when the worst comes true.

Unless and until you take the fast to the extreme and/or you completely give up strength training (thereby signaling to the body that you do not need those muscles), you will be burning fat.

Despite all of the above, we are constantly told that we need to eat 130 g of carbohydrates every day “for our brains to function properly”. This is utter rubbish, as I probably should have had dementia by now if this was true.


we are constantly told that we need to eat 130 g of carbohydrates every day 'for our brains to function properly'. This is utter rubbish, as I probably should have had dementia by now if this was true. Click To Tweet


Disclaimer: I am not telling everyone to fast and/or to restrict carbohydrates. Fasting is an absolutely amazing strategy to reverse the epidemic of obesity/insulin resistance that we presently have. Nearly 40% of our country is obese. Hence this post is published from a public health perspective, and his geared towards those who are struggling to lose weight.

If you are an athlete and are doing well on your program, I applaud you and hope you continue all the good work!


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